TABLE 3:
Freeze-fracture EM analysis of HeLa cells in an assembly assay versus reaggregation time.
| Cx43 cells | M257 cells | |||||
|---|---|---|---|---|---|---|
| 1 h | 3–3.5 h | 6 h | 1 h | 3–3.5 h | 6 h | |
| Initiation | ||||||
| Total number (%) of FPs plus mature GJ | 64 (100%) | 36 (100%) | 24 (100%) | 4 (100%) | 9 (100%) | 14 (100%) |
| Plaque area/FP (geometric mean, in μm2, with SEM) | 0.054 0.049–0.059 | 0.061 0.054–0.070 | 0.067 0.054–0.081 | 0.052 0.042–0.063 | 0.060 0.035–0.105 | 0.144 0.095–0.218 |
| Maturation | ||||||
| Number (%) of FP(−)s | 23 (36%) | 3 (8%) | 0 (0%) | 3 (75%) | 0 (0%) | 0 (0%) |
| Number (%) of FP(+) | 39 (61%) | 26 (72%) | 13 (54%) | 1 (25%) | 7 (78%) | 9 (64%) |
| Number (%) of mature GJs | 2 (3%) | 7 (19%) | 11 (46%) | 0 (0%) | 2 (22%) | 5 (36%) |
| Total number of aggregates in FP(+)s | 49 | 38 | 23 | 1 | 11 | 28 |
| Area/mature GJ (μm2, geometric mean, with SEM) | 0.068 0.042–0.110 | 0.008 0.006–0.011 | 0.013 0.011–0.021 | NA0 | 0.013 0.005–0.035 | 0.005 0.004–0.006 |
| Packing density of aggregated particles in FP(+)s (geometric mean, per μm2, SEM) | 6569 6225–6933 | 7780 7743–8131 | 8952 8595–9324 | 5574 NA | 7288 6972–7618 | 7577 7109–8074 |
| Density of unaggregated particles/FP(−) (geometric mean, per μm2, SEM) | 904 823–993 | 1051 719–1537 | NA NA | 375 366–384 | NA NA | NA NA |
| Density of unaggregated particles/FP(+) (geometric mean, per μm2, SEM) | 606 558–659 | 480 422–546 | 559 489–639 | 117 NA | 150 110–205 | 181 141–234 |
| Growth | ||||||
| Unaggregated particles/FP (geometric mean, SEM) | 37 34–41 | 32 26–38 | 37 30–47 | 14 9–23 | 9 7–12 | 26 21–33 |
| Aggregated particles/FP(+) (geometric mean, SEM) | 38 32–46 | 79 64–99 | 69 54–89 | 35 NAb | 36 28–47 | 103 (78)a 74–144 |
| Total particles/FP (geometric mean, SEM) | 63 56–70 | 119 100–142 | 114 92–142 | 26 21–32 | 49 39–61 | 138 (108)a 103–185 |
| Total particles/mature GJ (geometric mean, SEM) | 446 330–603 | 70 49–99 | 107 81–141 | NA NA | 81 48–117 | 49 39–62 |
| Total particles/(FPs plus GJs) (geometric mean, SEM) | 67 60–75 | 107 92–125 | 111 94–131 | 26 21–32 | 55 43–70 | 95 (80)a 75–122 |
See Materials and Methods for details related to EM sampling. The three GJ assembly parameters evaluated here are described in the Results section. Because the values for the areas of FPs and mature GJs, the numbers of particles found within them, and densities are skewed, the mean values for these features are expressed as geometric means (see Materials and Methods). Statistical values derived from t tests for various parameters are found in the Results section.
aIn these samples, there were small numbers of FP(+)s, including one large outlier in each case. When this value is not included, the geometric mean for the sample is shown in parenthesis.
bOnly one FP(+) in this sample.